1. Field of the Invention
This invention relates to a power generating device which converts unused heat energy having a temperature from 15.degree. C. to 200.degree. C. such as warm water like waste water discharged from factories, heat discharged from light water reactors and the like, waste heat discharged from gas having middle to low temperature and heat of terrestrial heat energy into heat having a higher temperature from 80.degree. C. to 500.degree. C. by using hydrogen absorbing and releasing actions of hydrogen absorbing alloys, and transmits the heat to a heat medium for a vaporization so that thus obtained vapour drives a turbine to generate power, and can be universally used as a system for converting unused energy to generate power.
2. Description of the Related Art
As one of prior power generating devices using a turbine, a device employing power of a turbine driven by vapour of a heating medium is generally and universally used.
In such a power generating device employing a gas turbine, power generation can be effected in the manner that cooling medium vapour such as steam, ammonia, fluorocarbon, or vapour obtained by vaporizing heating medium such as natural gas with heat is pressed and introduced into the gas turbine to drive the gas turbine, discharged vapour from the gas turbine is cooled and condensed, and thus obtained liquid medium is re-heated to be circulatively introduced into the gas turbine as pressed vapour. In the device, however, a temperature difference between a heating temperature and a cooling temperature should be extremely great, namely 100.degree. C. or greater. In fact, it is difficult to drive the gas turbine of the device with a heating source having a temperature of about 150.degree. C. and a cooling source having a temperature from 10 to 30.degree. C. due to extreme poor thermal efficiency and high cost of equipment.
A power generating device employing hydrogen absorbing alloys which makes use of power of a turbine driven with hydrogen gas has been developed in these years.
In such a power generating device making use of a hydrogen gas turbine, power generation can be effected in the manner that a device loaded with a hydrogen compound of a hydrogen absorbing alloy is heated with a heat source having a temperature from 300 to 350.degree. C. to introduce released hydrogen having a high temperature and a high pressure so as to drive the hydrogen gas turbine, and then discharged hydrogen from the hydrogen gas turbine is introduced into another device loaded with a hydrogen absorbing alloy and absorbed by the hydrogen absorbing alloy so that the device is also heated to circulatively introduce hydrogen having a high temperature and a high pressure into the hydrogen gas turbine. The device, however, has problems such that more hydrogen should be moved than in a heat pump employing hydrogen absorbing alloy, and high temperature from 300 to 350 .degree. C. should be used on the side of the heat sources, thereby a temperature to release hydrogen rises, thermal efficiency becomes very poor, employed hydrogen absorbing alloys are rapidly deteriorated and declined in quality and durability, and cost of equipment is increased.
In issued U.S. Pat. Ser. No. 6,141,966, to set the utility temperature of the low waste beat 30.degree. C. to 60.degree. C. and high waste heat 80.degree. C. to 90.degree. C. as specific restricted range has as the feature of the present invention been recognized definitely. Also, hydrogen absorbing alloy that is used accordingly, is specified as an alloy of Mish metal-nickel system. However, from now on, the energy source will be supplied in the form of heat from atomic energy, nature energy and waste heat from factories instead of fossil fuel. For example, it may gain heat from a high temperature gas furnace having a temperature below 1000.degree. C., heat from a light-water reactor having a temperature below 300.degree. C., heat from middle to low temperature gas having a temperature 150.degree. C. to 400.degree. C., heat from geothermal energy having temperature below 400.degree. C., heat from solar heat having a temperature below 100.degree. C. that is gained from a solar heat collection device and heat from waste water having a temperature 0.degree. C. to 100.degree.C. Heats that are gained like this have a great variety. Also, in a flow of energy present, about two third of the heat energy (nature energy is not included) is hardly used and is wasted, and its heating value is huge. Using these heats effectively will be a big problem in energy development in future.
The present invention is to solve the above mentioned problems of the prior power generating devices and has an object to provide an economical power generating device with high thermal conversion efficiency which can be used in various fields.